I'm using the $# feature to shrink an array. After shrinking to half the size, the array seems to take a bit more memory. How is that possible? (perl 5.10 on 64-bit GNU/Linux)

use strict;
use warnings;
use feature qw(say);
use Devel::Size qw(size);

my @array = 1 .. 10_000;
say size(\@array);
$#array = 5_000;
say size(\@array);
[download]

80064
80216
[download]

Is there a way to shrink the array without causing it to grow (and probably be reallocated)?

UPDATE: It seems splice doesn't cause the same effect.

my @array = 1 .. 10_000;
say size(\@array);
splice @array, 5_001;
say size(\@array);
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Output:

80064
80064
[download]

Furthermore, after running a few simple benchmarks, it turns out the splice method is about as fast as last index assignment, so it seems splice doesn't do unnecessary copying in void context.